package com.hroze.util.web;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * 验证码 servlet
 * 
 * @author ahoo
 * 
 */
public class ImageServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	public static Color getRandColor(int fc, int bc) {
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	public static void main(String[] args) throws IOException {
		File f = new File("c:\\a.jpg");
		FileOutputStream out = new FileOutputStream(f);
		int width = 60, height = 20;
		BufferedImage Image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		Graphics g = Image.getGraphics();
		Random random = new Random();
		// 图片背景色
		g.setColor(getRandColor(240, 250));
		// 干扰线样色
		g.fillRect(0, 0, width, height);
		g.setColor(getRandColor(185, 200));
		// 干扰线数量
		for (int i = 0; i < 5; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int x1 = random.nextInt(12);
			int y1 = random.nextInt(12);
			g.drawLine(x, y, x1, y1);
		}
		String Srand = "";
		// 写出四个数字
		for (int i = 0; i < 4; i++) {
			String rand = String.valueOf(random.nextInt(10));
			Srand += rand;
			g.setColor(new Color(random.nextInt(5), random.nextInt(5), random
					.nextInt(5)));
			g.drawString(rand, 13 * i + 6, 16);
		}
		g.dispose();
		ImageIO.write(Image, "JPEG", out);
	}

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws IOException {
		response.setContentType("image/jpeg");
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);

		int width = 60, height = 20;
		BufferedImage Image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		Graphics g = Image.getGraphics();
		Random random = new Random();
		g.setColor(getRandColor(240, 250));
		g.fillRect(0, 0, width, height);
		g.setColor(getRandColor(185, 200));
		for (int i = 0; i < 10; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int x1 = random.nextInt(12);
			int y1 = random.nextInt(12);
			g.drawLine(x, y, x1, y1);
		}
		String Srand = "";

		for (int i = 0; i < 4; i++) {
			String rand = String.valueOf(random.nextInt(10));
			Srand += rand;
			g.setColor(new Color(random.nextInt(5), random.nextInt(5), random
					.nextInt(5)));
			g.drawString(rand, 13 * i + 6, 16);

			HttpSession session = request.getSession();
			session.setAttribute("user_msg", Srand.toString());
		}
		g.dispose();
		ImageIO.write(Image, "JPEG", response.getOutputStream());
	}

}
